Conventionally, imaging apparatuses perform de-Bayer processing (de-mosaic processing) on raw image information (RAW image) captured by an image sensor, convert the image into signals including luminance and color difference, and perform so-called development processing including noise removal, optical distortion correction, and image optimization for each signal. Generally, after such development processing, the luminance and color-difference signals are compressed and coded and are finally recorded in a storage medium.
Other conventional imaging apparatuses are capable of recording RAW images. When a RAW image is recorded, a large amount of data needs to be recorded. However, since correction of or deterioration of original images can be minimized and RAW images can be edited after being captured, which are advantages in recording RAW images, advanced-level users preferably use this type of imaging apparatuses.
Japanese Patent Application Laid-Open No. 2011-244423 discusses an imaging apparatus capable of recording RAW images. According to Japanese Patent Application Laid-Open No. 2011-244423, development parameters are recorded along with a RAW image, and when reproduction is performed, these development parameters are used to develop and reproduce the RAW image.
In recent years, imaging apparatuses have been equipped with more advanced image sensors, and the number of pixels per image has been significantly increasing. In addition, a trend is that the number of images that can be continuously captured per second is increasing. Thus, the amount of processing including de-Bayer processing on a RAW image and development processing such as noise removal and optical distortion correction are synergistically increasing. As a result, performing real-time development processing simultaneously with an image capturing operation requires more circuits and power consumption. Development processing requires a larger circuit area or imposes constraints on power consumption. Therefore, in some cases, high image capturing performance cannot be achieved.
On the other hand, as discussed in the above Japanese Patent Application Laid-Open No. 2011-244423, if a RAW image is recorded without being developed, the amount of processing required for development during the image capturing operation could be reduced. However, since the RAW image is recorded without being developed, it is difficult to promptly reproduce and display the image. In addition, because of the particularity of data unique to RAW images, the RAW images may not be reproduced (developed) by other devices. Namely, with conventional RAW image recording methods, user-friendliness could be deteriorated.
Thus, there are problems to be addressed for enabling conventional apparatuses to achieve high image capturing performance and to promptly display reproduced images. That is, it is necessary to mount high-cost circuits on the apparatuses and to drive the apparatuses with higher power or RAW images need to be recorded and reproduced promptly and simply.